Excel 2007 : Combining text and number columns into one

I'm self taught with Excel, so forgive me if this is a very rudimentary question.

I need to combine information from two columns into one column. For example, in column one I have ABC. In column two, I have 123. I need to combine this information so it reads ABC123. Is there a way to do that?

Try:

=A1&B1

where A1 and B1 are the first 2 to combine, then copy the formula down by dragging the little black square in the right bottom corner of the cell down the column... if that is required.